Cite
APA Citation
Katz, D. L., Jekel, J. F., Elmore, J. G., Wild, D. M. G., & Lucan, S. C. (2014). Jekel's epidemiology, biostatistics, preventive medicine, and public health. Philadelphia, PA : Saunders, an imprint of Elsevier Inc. http://access.bl.uk/ark:/81055/vdc_100037504247.0x000001